Air filter



Nov. 10, 1925. 1,560,790

A. JORDAHL AIR FILTER Filed May 1o. -1924 Fleas, fm" J Slifer new Patented Nov. l0, 1925.A

UNITED STATES PlriaNrV oFFlcE.

ANDERS JOBDAHL, 0F NEW YORK, N. Y:

AIR FILTER.

Application led Hay 10, 1924. Serial No. 712,280.

To all whom it lmay cof/teem:

Be it known that l, ANDERS JoRDAHL, a subject of the King of Norway, residing at New York, in the county and State of New York, have invented certain new and useful improvements in Air Filters, of which the following is a specification.

The present invention relates to air and gas lters of the type employing a fibrous material as a filter medium, such medium ben ing metal wool; shavings of steel, monel,

aluminum, copper or brass, etc.; or it may be asbestos or other natural or artificial mineral wool, or animal or vegetable fibre. Such materials have heretofore been-packed into the filter cells in a loose and free state which of course sets up many disadvantages, some of which may be mentioned as follows. lt

is a difficult matter to pack the fibre in a comparatively large area, such as a filter cell which is generally 1.8` 'by 18", in order to obtain a layer of uniform density and furthermore difficulties arise when such a layer of fibre is to be washed, after it has become `of fibre has a tendencyto settle whereby the lower strata. are compressed but the upper strata are porous of which the top may even be empty. `It is also a fact that almost any kind of fibre arranged in a layer'of large area will lose its uniformity of structure in the course of a washing process as some of it will disintegrate and be carried away with the washing liquid and some of it will form into tufts of a greater density, all of which will give it a spotted appearance when-held against a light. It is also necessary to re-` new the fibre from time to time and this can only be successfully accomplished by experienced men. v

The above objections are overcome by forming the fibrous material of the filter cell into a plurality of small mats each of which isenclosed in a casing of fine mesh wire netting or in thin perforated sheets, or fine mesh expanded metal and the like. These mats are preferably made thin and narrow but of .a length equal to the width of the filter cell. A further object of this invention is to so construct the cell in order that Vthe mats may be removed for individual -ilter media of varying coarseness and consequently of varying density. Further objects will be apparent from the following specification taken in connection with the accompanying drawing in which like reference characters indicate corresponding parts throughout, and in which:

Figure l is a front view of theilter unit,

F ig. 2 is a section of the unit taken on line 1 1 of Fig. 1,

Fig. 3 is a detail of a part ofthe mat on an enlarged scale and partly broken away,

Fig. 4: is a section of a part of the unit showing another form of amat, and

Fig. 5 is a detail of a part of the mat of Fig. l on an enlarged scale and partly broken away.

This filter apparatus is built in the form of units and since this invention resides in the specific .construction of the unit the specification and drawing have been limited to a single filter unit. -This unit comprises a' frame 1 having flanges 2 and 3 bent at right angles but in opposite'directions to the web portion 4. In this frame a per-V forated plate 5 is provided which is adapted to be inserted against the flange 2 and this plate is provided with suitable perforatlons 6. This plate is shown only by way of enample since a screen or other suitable means could be employed. The frame is adapted These mats 7 comprise a casing 10 of a suitable wire netting which encloses the filter medium 11. Any suitable method can be employed in making these mats such as wrapping the vnetting around the filter medium and then soldering it together to be then pressed into the desired shape or the casing can 'first be made after which the filter medium can be pressed therein. It is of course understood that the word mat through the filter cell. YVhile the mats are may include any filter material as outlined in the opening paragraph. l

Figs. 4 and 5 show another form of filter mat which is also enclosed Vin a Wire casing 10 but which is provided with a plurality of layers of iltermedia of varying doarseness. Layer 12 is the coarse layer, 13 the medium, and 14 the fine layer, the object-being that the coarse layer is placed toward the dirty air or the outside and the fine layer on the inside as shown in Fig; 4, the arrows representing the direction ot' the air Icurrent shown as arranged on their sides in Fig. 4 instead of on their ends as in Figs. 1 and 2 it is however understood that they can be arranged in any suitable mzgmcr and each mat can be made in any desired shape and thickness whereby also the. number `'of mats iior each unit can be varied depending upon the service required. Layers l2, 13 and 14 can also be varied in number and each layer may be provided with a'casing of wire netting, not shown, thus allowing the individual layers to be removed from the casing by a suitable opening, not shown, at the end.

The chief advantagesproduced by this invention resides in the production of a layer of fibrous material of uniform thickness and of a uniform density which pre-I vents settlement of the fibrous material. Furthermorel the individual mats .can be removed fromtherfilter frame for washing purposes and since theA lter medium is packed into'comparatively small mats none of the material can Wash away. These mats being interchangeable they can be easily replaced when necessary and this can' be done by unskilled labor thus reducing the cost of upkeep. It will'therefore be lseen that b'y the use of aplurality of small mats into which th'e fibrous material is packed, new and important results are obtained Which'conld not be obtained in filter units wherein the fibrous material is inserted in a loose state. v

I claimA as my invention:

1. An air filter comprising a frame; a

of mats in said frame and against said plates; and a plurality ot bars 1n sald frame for securlng said mats 1n place.

2. An air filter 'comprising a frame; a

perforated plate, secured 'in said frame; a plurality of Wire-net casings arranged in parallel relation in said frame; a filter medium in each-casing; and means for re- `screen-like plate in sid` frame; a plurality Y .movablyl securing said casings in said 4. An air filter comprising a frame; a perforated plate in said frame; a plurality of lmats in said frame and against said plate; and a plurality of bars adapted to be secured in said frame for removably securing said mats in said frame, each mat having a plurality of layers of filter media of different densities therein.

In testimony whereof I affix my signature.

ANDERS JORDAHL. 

